joeq wrote:Figured this title would bring in all the Sheldon Cooper fans. (Big bang theory). Was curious about the theory or opinions on this. Concerning draft and/or rising heat out of our stoves. The more air flowing through the coal bed, usually dictates the intensity of the fire. More air equals more heat. (Providing enuff fuel to support it). Air in usually also requires air out. I've been skooled here that, if we close down our MPD, then more heat will be retained into the stove. (Makes sense to me). However, if closing the MPD slows down the draft, then the stove can't produce the required amount of heat to build the fire. I'm wondering about which phenomenon has a larger potential for heat output. Close down the MPD, to retain heat, but lose the higher draft, or open the MPD for a higher draft, but send the hot air up the chimney? Which is the preferable method?

Well,being I'm a Combination of an Aspiring Alzheimers' Patient/Concentration Deprivation Candidate,and just a General Mental Trainwreck,Look Out,here's my take..... The Fuel dictates the Flow Method of Control. The Stove Design and Total Thermal Mass available to radiate outward allows the heat produced to leave the unit,thereby getting the most productive heat output from the stove without sending heat up the flue. Baseburners come to mind.Keep in mind that the MPD and Baro are tools of Flow Control. Their Complimentary Tools are your Combustion Air Inlet Controls. If the Stove has been constructed and maintained as an Air Tight,Theoretically those Control Tools are the only way to conduct flow. So the preferable method is no single method is ultimately correct. Sorry to do it to you,but the MPD has carried the day forever. It went as far as it could. It seems to me that the Baro was developed to compensate for Windy,Gusty Days trying to suck or draft the Living Daylights out of the Stove and its Fuel Supply. The Stove lacked the ability to Control Combustion Air due to the Higher Vacuum trying to pull through the Stove.....I love definite situations,but this one seems to be an Eternal Grey Area. In closing,I'm so full of crap that my eyes are brown!

Hambden Bob wrote:Sorry to do it to you,but the MPD has carried the day forever. It went as far as it could. It seems to me that the Baro was developed to compensate for Windy,Gusty Days trying to suck or draft the Living Daylights out of the Stove and its Fuel Supply. The Stove lacked the ability to Control Combustion Air due to the Higher Vacuum trying to pull through the Stove.....I love definite situations,but this one seems to be an Eternal Grey Area.

How Do You Think We Feel !! In reality,nothing ever frees us from mastering our ever changing situations. The Book may tell us the fast and hard Educated Rules,but Field Conditions that toss in Variables causes us to unlock the Actual Answers. An open campfire with a ring of stones around it is easy. We,as CoalBurners,enjoy doing it right. That's where Herr Sting comes in so Handy with some of his Theories. That Rotten Freetown Fred tosses out some of that there 'Ol Native Farmer Technology of the Simple and Actual Laws Of Living. This Board is so much more than the Treasure Trove of Black Rocks Knowledge. All of you offer Great Perspective on Everyday Living Of The Life! It's a Pleasure to Stand With You All on This Here Digital Porch !

'Taint Nuthin' To It,Menses ! Wish I could blame it on Drinkin' or Simple,Ignorant Substance Abuse! I do believe it's Dain Bramage fer sure! The Boys at Work tell me that I simply Speak"Hambden Bob-bonics" ! Hell........ .......Here's To All Of You Draft-Masters out there,making it Flow in a very Dangerous World!!

I really dont know the answer and never will. But, with a stove without a baro damper, just a MPD, if I leave the MPD wide open it may or may not put out the same amount of heat as the same stove with the MPD closed all the way. it might slow down the heat or it might speed it up, BUT, I'm pretty sure that the stove with the damper wide open will go out first, before the one with it closed. That means I'm heating my house longer with it closed, even if they put out the same amount of heat(BTU). So, im leaving mine closed.

Something I am familiar with - a young product spreading its way through internet gossip, is a new design of chimney cowl, invented by a New Zealander. It targets the inversion condition and how it causes negative pressure, typically on a normal vertical, cylindrical flue pipe. NIL has been researched at this end, as far as emissions and efficiency is concerned. He has had a hard time, in conflict with future projected investments in alternative fuels and the appliance selling industry itself. The original UL standard that went national ignored everything from the flue connection upward and didn't test for winter conditions. Good, optimum - clean combustion requires ventilation that addresses the negative impact of inversion. It cannot all be fixed inside the appliance. The environmentalists all sing in chorus about inversions trapping smoke, and are clueless in regards to the inversion causing it. The appliance manufacturers couldn't care - not their problem. Shove a green sponsored catalytic combustor in it and voila! Oddly the regulators still continue their anti-wood 'burning' social marketing regimes for natural gas fuel expansionism. Wood - biomass (if you'd rather) is environmentally cleaner hands down. It's the technique that makes the method clean, not the fuel. Biomass looks good. It grows trees, managers and diversifies plantations - can be self sufficient, and with all the right elements applied to the technique, it is very clean as well as sustainable. A conventional burner with a vertical cylindrical flue needs a pressure differential on the terminal to keep the vacuum conditions consistent inside the flue/ exhaust. Without it the optimum combustion conditions will always be compromised by naturally forming, winter inversion negative pressure. To address down draft, blow back, creosote, sooted up catalytics and remaining smoke issues do something the EPA, Omni, and the HPBA are failing consumers at doing. Look at the external ventilation in respect to the weather conditions.